Bit-brace



(No Model.)

J. CHANTRBLL'; BIT BRACB.

Patented Sept. 1, 1888.

.mkh 2 y# E e, l Y U E UNI-TED STATES PATENT OFFICEa JOHN CHANTRELL, OF nmnenronr, oONNnorrcUT, AssreNOn To HAZELTINE e a OHANTRELL, OF sAMn PLACE.

, `BIT-FRAGE.

SPECIFICATION formingpart `of `Letters Patent No. 284,276, dated September 4, 1 883.

Application filed March 2, 1853. (No model.) l l To `cir/ZZ whom, it may con/cern.-

Bridgeport, rin the county of `Fairfield and State of Connecticut, have invented certain new and Vuseful Improvements in litdraces;1 and I dohereby declare the following to be a full, clear, and exact description of the invention, such as will enable others` skilled in the art towhich it appertains to make and usethe same. v l

My invention relates tolan improvement in bit stocks or braces,\the obj ect of the same bengto` provide a device of few parts that;

will combine simplicity and economy in construction withdurability in use; and with these i ends in view my invention consists in the parts and combinations of parts, as will be" more `fullydescribed, and pointed out in the claims.

In the accompanying drawings, Figure l is a view Iin perspective of my improved brace.. Fig. 2 is a longitudinal view through the sock-` Veted end or head thereof 5' and Fig. 3 isa detached view ofthe bit-holder, the followers, and screw, all of the parts being in theirproper relative positions. j A represents the handle of the bit-stock,

which is of ordinary shape, the outer o'r free `andis provided with the oblong slots a,through which themilledledges of the operating-wheel C project, to enable the operator to adj ust the parts when desired. This head is provided, near its outer end, on opposite sides, with the inclined planes c, against which the outerbeveled ends of the holders E E bear,while the inner end of the said head is provided with the inwardly-converging` inclined planes d d, against which the lower beveled ends of the followers `D D bear, and against which they` move. The inclined planes o and d` come, respectively, above and below the large side opening in the head` and form the limits of said opening. The outer open end of the head is sufficiently large for the insertion of the shank of abit, butis toc small for the passage of the bitholders `or jaws, which latter are v i introduced in position through tlfe large side 5o Be it known that I, JOHN GHANTRELL, ofi

opening. The wheel C is provided centrally i with an angular opening, into which the rightand-lefthand screw Dwhich is provided centrally with an angular portion corresponding in shape to the angular opening in the wheel 55 C, is secured. Thiswheel C is first placed in position within the head, and the screw driven therein until the angular portion thereof rests within the angular `opening of the wheel. The

opposite ends of the screw D2,\after the latter 6o .is secured in position, project from both sides of the wheel and control the'movements of the followersDfD, which latter rest` in the large openings on opposite sides ofthe head and on opposite sides of the wheel. These follow- 65 ers D `D are provided with the `beveled ends g and central hubs, h h, one of which latter is provided with a right-hand female screw, and is consequently adapted to register with the end of the screw having the right-hand 7o and the two depressions combined into one, a

space sufficiently large is formed, into which the wheel C rests. This construction enables the 8O followers to be drawn suiciently close together to clamp `a small bit-shank therein` The bit-holders E E are shaped alike, each being provided on its outer side with the beveled ends jj', the outer beveled ends, j, bear- 85 i ing against the inclined planes c, whilethe inner beveled edges, j, rest between the beveled i edges g of the followersDD. The inner .faces of both holders E E are grooved. for the reception of the end ofthe bit-shank, and each 9o is also provided with a shoulder, 7c, adapted to firmly embrace the bit 4above its shoulder Z and prevent it from being accidentally with*- drawn from position. The holder Eis provided on opposite sides with `the arms 171,95 which latter rest in the grooves n., formed in the sides of the holder E, and hold both jaws in the same horizontal position, which prevent Y one jaw or holder from falling down lower than the other.

The wheel C is first placed in proper position and the screw D2 inserted therein. The jaws or holders are then introduced through one of the large side openings in the head and `moved upward .into position, and finally the followers' are placed against the opposite ends of the screw. Now, by turning the wheel C, both followers (engage with their respective screws and are drawn toward each other, maintaining, however, their parallelism throughout their entire movement. As the screw is turned the followers are, by'their contact with the inclined planes d, forced toward the outer end of the head. rIhis outward movement of the followers also causes the holders or jaws to move lengthwise or endwise in the same direction. As the jaws are moved outward their upper beveled ends come in contact with the inclined planes c, which latter, together with the beveled ends g of the followers, force the holders or jaws together and firmly clamp the sh ank ofthe bit therein irrespective ofthe shape of the latter. Vhen it is desired to release the bit, the wheel C is turned in the opposite direction, which allows the followers to movedown the inclined planes el and the jaws to move back between the ends g of the followers and away from the inclined planes c. After the jaws leave the inclined planes c, they separate or fall apart and leave the bit free to be withdrawn. Y

Instead of providing the socket with the inclined surfaces c and d, pins, with or without friction-rollers thereon` can be passed transversel'y through the head and perform the functions of the inclined planes, my main object being to clamp the jaws together and center the bit, and both can be accomplished as well with one as the other.

This device is exceedingly simple in construction, is durable and effective in use, can be manufactured at a small initial cost, and can be quickly and easily operated.

It is evidentthat slight changes in the eon` struction and relative arrangement of the several parts might be resorted to without departing from the spirit of my invention; and hence I would have it understood that I do not confine myself to the exact construction shown, but consider myself at liberty to make such slight changes and alterations as fairly fall within the spirit and scope of my invention.

Having fully described myinvention, what I claim as new, vand desire to secure by Letters Patent, is-

l. In a bit-brace, the combination, with the socket and holding-jaws, of followers constructed to engage the holding-jaws and impart lengthwise movement thereto, and means for operating the followers, substantially as set forth.

2. In a bit-brace, the combination, with the socket and holding-jaws, having inclined or beveled rear ends, j', of followers provided with beveled ends that engage the rear ends of the holding-jaws, and means for drawing the followers together, substantially as set forth.

3. In a bit-brace, the combination, with the socket and holding-jaws, having inclined or beveled rear ends, j', of followers, each having its opposite ends beveled or inclined, one

inclined end of the follower arranged to engage the beveled end of the holding-jaw andY the opposite end thereof to engage an inclined bearing-face on the socket, and meansy for drawing the followers together and imparting endwise movement to the holding-jaws, substantially as set forth.

4. In a bit-brace, the combination, with the socket having inclined bearing-faces at its outer end, and holding-jaws constructed with inclined faces on their opposite ends, of followers provided with inclined ends, and a right-and-left-hand screw for forcing the fol- Y lowers toward and away from each other, substanti ally asset forth.

5. In a bit-brace, the combination, with a socket having inclined faces at its opposite ends, and holding-jaws arranged to engage the inclined faces on the outer end of the socket, of followers constructed to engage the inner ends of the holding-jaws and the inner inclined faces on the socket, and a right-andleft-hand screw for operating the followers, substantially as set forth.

6. In a bit-brace, the combination, with a slotted socket, holding-jaws, and followers, of a right-and-left-hand screw and a thumbwheel that projects through the slots in the socket, substantially as set forth.

7. In a brace-bit, the combination, with a socketed head, of the clamping-jaws, one of which is provided with side arms which rest in corresponding grooves in the other jaw, and devices for clamping a bit-shank between the said jaws.

In testimony whereof I have signed this specification in the presence of two subscrib- Vitnesses G. F. DowNING, S. G. NOTTINGHAM.

IOO 

